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Topic: Landing Gear oleo servicing 391B (Read 204 times)

My POH is missing these critical pages for servicing the landing gear struts (see below: poh ref to pp 42 and 43A which are missing)s. We seem to have a persistent droop on the right main gear and I am looking for an A&P in Texas near Houston who can advise me or show us the technique.ThanksBill

It says to inflate main shock to 3.88 to 4.00 inches " to top of cylinder, but we don't know what is the normal expected pressure range for the high pressure nitrogen. Does anyone have guidance on the expected pressure to reach 4.00 or perhaps this comes from experience? Unless I am missing something the " sufficient servicing information" does not appear on this version of page 42 (page 43A is for the tailwheel)ThanksBill

I checked the military manual to see if it had more information on servicing and it really doesn't. What I do is put the main gear on a set of grease plates so the gear can move easier. With the struts serviced with hydraulic fluid, put nitrogen in while having someone gently rock the aircraft at the wing tip. It will take almost 1000 psi of nitrogen to raise the aircraft. If you over inflate, you can open the valve a bit and let some nitrogen out but be careful as it happens fast! 3.88" to 4.00" is a good reference point but more importantly is is having the wing tips at the same height. I either measure them to the ground or since I'm short, I add three fingers to my height. After many years of operation and probably a few "adjustments" to the cabin structure, the 3.88-4.00" might or might not work. The tail strut takes a lot less pressure. Jim